Pgvector v0.3.1 — nugetz

dotnet add package Pgvector

var dataSourceBuilder = new NpgsqlDataSourceBuilder(connString);
dataSourceBuilder.UseVector();
await using var dataSource = dataSourceBuilder.Build();

var conn = dataSource.OpenConnection();

await using (var cmd = new NpgsqlCommand("CREATE EXTENSION IF NOT EXISTS vector", conn))
{
    await cmd.ExecuteNonQueryAsync();
}

conn.ReloadTypes();

await using (var cmd = new NpgsqlCommand("CREATE TABLE items (id serial PRIMARY KEY, embedding vector(3))", conn))
{
    await cmd.ExecuteNonQueryAsync();
}

await using (var cmd = new NpgsqlCommand("INSERT INTO items (embedding) VALUES ($1)", conn))
{
    var embedding = new Vector(new float[] { 1, 1, 1 });
    cmd.Parameters.AddWithValue(embedding);
    await cmd.ExecuteNonQueryAsync();
}

await using (var cmd = new NpgsqlCommand("SELECT * FROM items ORDER BY embedding <-> $1 LIMIT 5", conn))
{
    var embedding = new Vector(new float[] { 1, 1, 1 });
    cmd.Parameters.AddWithValue(embedding);

    await using (var reader = await cmd.ExecuteReaderAsync())
    {
        while (await reader.ReadAsync())
        {
            Console.WriteLine(reader.GetValue(0));
        }
    }
}

await using (var cmd = new NpgsqlCommand("CREATE INDEX ON items USING hnsw (embedding vector_l2_ops)", conn))
{
    await cmd.ExecuteNonQueryAsync();
}

dotnet add package Pgvector.Dapper

using Pgvector.Dapper;

SqlMapper.AddTypeHandler(new VectorTypeHandler());

var dataSourceBuilder = new NpgsqlDataSourceBuilder(connString);
dataSourceBuilder.UseVector();
await using var dataSource = dataSourceBuilder.Build();

var conn = dataSource.OpenConnection();

conn.Execute("CREATE EXTENSION IF NOT EXISTS vector");
conn.ReloadTypes();

public class Item
{
    public int Id { get; set; }
    public Vector? Embedding { get; set; }
}

conn.Execute("CREATE TABLE items (id serial PRIMARY KEY, embedding vector(3))");

var embedding = new Vector(new float[] { 1, 1, 1 });
conn.Execute(@"INSERT INTO items (embedding) VALUES (@embedding)", new { embedding });

var embedding = new Vector(new float[] { 1, 1, 1 });
var items = conn.Query<Item>("SELECT * FROM items ORDER BY embedding <-> @embedding LIMIT 5", new { embedding });
foreach (Item item in items)
{
    Console.WriteLine(item.Embedding);
}

conn.Execute("CREATE INDEX ON items USING hnsw (embedding vector_l2_ops)");
// or
conn.Execute("CREATE INDEX ON items USING ivfflat (embedding vector_l2_ops) WITH (lists = 100)");

dotnet add package Pgvector.EntityFrameworkCore

using Pgvector.EntityFrameworkCore;

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.HasPostgresExtension("vector");
}

protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
    optionsBuilder.UseNpgsql("connString", o => o.UseVector());
}

public class Item
{
    public int Id { get; set; }

    [Column(TypeName = "vector(3)")]
    public Vector? Embedding { get; set; }
}

ctx.Items.Add(new Item { Embedding = new Vector(new float[] { 1, 1, 1 }) });
ctx.SaveChanges();

var embedding = new Vector(new float[] { 1, 1, 1 });
var items = await ctx.Items
    .OrderBy(x => x.Embedding!.L2Distance(embedding))
    .Take(5)
    .ToListAsync();

foreach (Item item in items)
{
    if (item.Embedding != null)
    {
        Console.WriteLine(item.Embedding);
    }
}

var items = await ctx.Items
    .Select(x => new { Entity = x, Distance = x.Embedding!.L2Distance(embedding) })
    .ToListAsync();

var items = await ctx.Items
    .Where(x => x.Embedding!.L2Distance(embedding) < 5)
    .ToListAsync();

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity<Item>()
        .HasIndex(i => i.Embedding)
        .HasMethod("hnsw")
        .HasOperators("vector_l2_ops")
        .HasStorageParameter("m", 16)
        .HasStorageParameter("ef_construction", 64);
    // or
    modelBuilder.Entity<Item>()
        .HasIndex(i => i.Embedding)
        .HasMethod("ivfflat")
        .HasOperators("vector_l2_ops")
        .HasStorageParameter("lists", 100);
}

dotnet add package Pgvector

open Pgvector

let dataSourceBuilder = new NpgsqlDataSourceBuilder(connString)
dataSourceBuilder.UseVector()
use dataSource = dataSourceBuilder.Build()

dataSource
|> Sql.fromDataSource
|> Sql.query "CREATE EXTENSION IF NOT EXISTS vector"
|> Sql.executeNonQuery

dataSource
|> Sql.fromDataSource
|> Sql.query "CREATE TABLE items (id serial PRIMARY KEY, embedding vector(3))"
|> Sql.executeNonQuery

let embedding = new Vector([| 1f; 1f; 1f |])
let parameter = new NpgsqlParameter("", embedding)

dataSource
|> Sql.fromDataSource
|> Sql.query "INSERT INTO items (embedding) VALUES (@embedding)"
|> Sql.parameters [ "embedding", Sql.parameter parameter ]
|> Sql.executeNonQuery

type Item = {
    Id: int
    Embedding: Vector
}

dataSource
|> Sql.fromDataSource
|> Sql.query "SELECT * FROM items ORDER BY embedding <-> @embedding LIMIT 5"
|> Sql.parameters [ "embedding", Sql.parameter parameter ]
|> Sql.execute (fun read ->
    {
        Id = read.int "id"
        Embedding = read.fieldValue<Vector> "embedding"
    })
|> printfn "%A"

dataSource
|> Sql.fromDataSource
|> Sql.query "CREATE INDEX ON items USING hnsw (embedding vector_l2_ops)"
|> Sql.executeNonQuery

dotnet add package Pgvector

Dim dataSourceBuilder As New NpgsqlDataSourceBuilder(connString)
dataSourceBuilder.UseVector()
Dim dataSource = dataSourceBuilder.Build()

Dim conn = dataSource.OpenConnection()

Using cmd As New NpgsqlCommand("CREATE EXTENSION IF NOT EXISTS vector", conn)
    cmd.ExecuteNonQuery()
End Using

conn.ReloadTypes()

Using cmd As New NpgsqlCommand("CREATE TABLE items (id serial PRIMARY KEY, embedding vector(3))", conn)
    cmd.ExecuteNonQuery()
End Using

Using cmd As New NpgsqlCommand("INSERT INTO items (embedding) VALUES ($1)", conn)
    Dim embedding As New Vector(New Single() {1, 1, 1})
    cmd.Parameters.AddWithValue(embedding)
    cmd.ExecuteNonQuery()
End Using

Using cmd As New NpgsqlCommand("SELECT * FROM items ORDER BY embedding <-> $1 LIMIT 5", conn)
    Dim embedding As New Vector(New Single() {1, 1, 1})
    cmd.Parameters.AddWithValue(embedding)

    Using reader As NpgsqlDataReader = cmd.ExecuteReader()
        While reader.Read()
            Console.WriteLine(reader.GetValue(0))
        End While
    End Using
End Using

Using cmd As New NpgsqlCommand("CREATE INDEX ON items USING hnsw (embedding vector_l2_ops)", conn)
    cmd.ExecuteNonQuery()
End Using

var vec = new Vector(new float[] { 1, 2, 3 });

var arr = vec.ToArray();

var vec = new HalfVector(new Half[] { (Half)1, (Half)2, (Half)3 });

var arr = vec.ToArray();

var vec = new SparseVector(new float[] { 1, 0, 2, 0, 3, 0 });

var dictionary = new Dictionary<int, float>();
dictionary.Add(0, 1);
dictionary.Add(2, 2);
dictionary.Add(4, 3);
var vec = new SparseVector(dictionary, 6);

var dim = vec.Dimensions;

var indices = vec.Indices;

var values = vec.Values;

var arr = vec.ToArray();

git clone https://github.com/pgvector/pgvector-dotnet.git
cd pgvector-dotnet
createdb pgvector_dotnet_test
dotnet test

cd examples/Loading
createdb pgvector_example
dotnet run

ankane/Pgvectorv0.3.1

Get Started

Readme

pgvector-dotnet

Getting Started

Npgsql (C#)

Dapper

Entity Framework Core

Npgsql.FSharp

Npgsql (Visual Basic)

Reference

Vectors

Half Vectors

Sparse Vectors

History

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